Originally Posted by jvelos3

Now I'm confused, when WOT the ecu goes into open loop so it dumps a preset amount of fuel depending on how much air the MAF sees while the timing is RPM dependent. A more free flowing exhaust allows more air to pass the MAF, confuse the tune, and possibly run lean? But shouldn't the tune be able to see more air, dump more fuel, and correct for this? I live in Chicago and I've done a few pulls at 20-30F and my AFRs were exactly the same as during 90+F heat. I'd imagine that 20-30F vs 90+F ambient temp would make a much larger difference for the MAF than an exhaust change, right?

psychoballistic, did your friend have the older version of the turbonetics with the 380cc injectors? My tuner was surprised that I only have 380cc injectors. According to him I was already running ~85% duty cycle at my power levels. He did tune me a bit on the rich side (11.2ish) but he told me if I wanted to run more than 5psi I should get a return fuel system and get bigger injectors cuz I was "maxed out" if we were keeping things on the safe side. Maybe the injectors just weren't flowing enough to allow the ecu to compensate.

Originally Posted by psychoballistic

I agree with what your saying, however as Charles mentioned, there is no clear answer. I am just a firm believer in constantly making sure everything is adjusted to run the car optimal all the time.

I had a friend with a turbonetics on his G and when he went to a turbo Ti-c from the stock (much more restrictive yes) he was leaning out tremendously. I would hate to ever see someone have something go terribly wrong because it slipped their mind to look at the afr while making a pull or something of the sort. Again, personal preference varies for everyone, that is just me.

Originally Posted by jvelos3

I just got the agency power single exhaust installed. AFR's with nismo were ~11.3-.4. AFR's with AP are...~11.3-.4!!

The turbo really quiets down the AP. During normal driving its loudness peaks abruptly at 2k rpm but its super quiet from 2-3k! Haven't cruised on the highway in 6th gear yet but 2-3k in 4th is super quiet. WOT it sounds sooo mean!

Thanks everyone for the input.